1. Tune up before you get up.
- My least favourite opening to a jam session is "standard tuning in full volume". It wastes time when folk could be playing, and is extremely irritating to the audience. Don't forget, at a jam, it's likely a lot of your audience are musicians, and we KNOW you don't need to be putting us through this!!!
- Have an electronic tuner that is bright enough to see in low light since you might be at the side of a stage or still at your seat, and pubs are not often brightly lit.
- Don't assume your guitar is still in tune if you tuned before you left your house.
- If you put on new strings before playing live, stretch the heck out of them and re-tune. Then do it again. And again. Until the tuning stabilises. You don't want to have the strings go out of tune on your very first two-fret bend when you are on stage
2. Practice standing up.
- weird as it sounds, if you're in the habit of practicing sitting down, it can be hard to get used to playing standing up, facing forward and not being able to see the fretboard. Don't make your first jam the place where you find this out.
3. If you're planning on singing, practice into a microphone.
- If you have to spend your time on stage trying to figure out how to stand in front of a mic to sing into it, you will forget how to play and how to sing, and what the words are of your song
- When you practice, practice into a microphone. It doesn't matter if the mic is plugged in, although that does help. It doesn't even have to be a real microphone so long as it simulates the experience of standing in front of one and singling directly into it
- Don't be alarmed if you can hear yourself sing really loudly on stage. The sound guy will ensure you're not too loud or too quiet out front. But don't be afraid to ask for a change to the monitoring so you get what you need to be able to perform
In summary, the hardest part of playing on stage involves almost everything else that isn't about playing the guitar. It is an extremely alien environment until you're used to it.
For the record, I do all my practicing in front of a mic, standing up. I use amp modelling for the guitar, and both it and the mic are plugged into a small mixer and i monitor on a really good set of headphones, so that i can really hear what's going on.